Prepayment electricity-meter.



H. ARON. PREPAYMENT ELECTRICITY METER. APPLICATION FILED NOV. 13, 1906. RENEWED 00114, 1909.

957,535,, 1 Patented May 16,1910.

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HEBMANN ARON, OF CHARLOTTENBURG, GERMANY, ASSIGNOR TO THE AMERICAN ARON ELECTRICITY METER COMPANY, A CORPORATION OF NEW JERSEY.

PREPAYMENT ELECTRICITY-METER.

Specification of Letters Patent.

Patented May 10, 1910.

Application filed November 13, 1906, Serial No. 343,214. Renewed October 14, 1909. Serial No. 522,614.

T 0 all whom it may concern:

Be it known that I, I'IERMANN ARON, a citizen of the Empire of Germany, residing at 39 VVilmersdorferstrasse, Charlottenburg, in the Kingdom of Prussia and Empire of Germany, have invented certain new and useful Improvements in Prepayment Electricity-Meters, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to automatic prepayment meters operated in such a manner that, after a coin has been introduced into the apparatus, a drum or the like is moved by hand, which turns through the intervention of the coin an arbor of the automatic mechanism to a certain extent and closes an electric switch at the same time. As the electric current is consumed, the forward motion of the counting mechanism causes the arbor to turn backward to the same extent and the switch is released as soon as'the arbor has been brought back to its original position.

In the annexed drawings, Figure 1 is a partial front side view and Fig. 2 a partial plan view of the prepayment mechanism of an electricity meter embodying the present improvement.

In the pro-payment electricity meter illus trated by the accompanying drawing, the turning of the handle 1 (after a coin has been introduced into the apparatus) causes the rotation of the drum 2 containing the coin through the intervention of the coin bearing on the arm 3. The wheel 4; imparts motion to a toothed wheel 5 connected to its arbor 30 by means of a friction clutch, the turning of this arbor winding up the spring contained in the spring barrel 6. Then this spring is Wound up, its elasticity acts against the friction clutch and the wheel 5 rotates on the arbor Without rotating the arbor.

The axis 31 of the switch 8 which closes, or breaks, the circuit for the supply of current is connected by the toothed wheels 9 and 10 to the barrel 6. The switch would be constantly rotated by the wound-up spring 6 were it not prevented from doing so by a pin 11 which alternately comes into contact with two pins 12 and 13 on a lever 14. The arrangement is such that the switch is closed when the pin 11 bears on the pin 13 and the switch is open when the pin 11 bears against the pin 12. The work required to operate the switch is derived from the elasticity of the spring 6 after the lever 14 has been moved so as to release the switch. This movement of the lever 14: is caused by the arbor 16 connected by toothed wheels to the toothed wheel 17 fixed to the drum 2. The toothed wheel 17 meshes with a larger toothed wheel 32 fixed upon the spindle 33 which carries the toothed wheel 34 meshing with a wheel 35 of the planet wheel gearing presently to be described. When a coin has been inserted in the apparatus and the handle 1 has been rotated, the arbor 16 is rotated to an extent which corresponds to the number of the coins successively inserted in the apparatus. The counting mechanism returns the arbor 16 to its initial position when currentis being consumed, the said counting mechanism being connected to this arbor in any suitable manner, for instance by planet wheel gearing so contrived that the wheel 17 drives one of the crown wheels 36 through the several intermediate wheels while the other crown wheel 37 is connected with the counting mechanism through intermediate wheels 38 and 39, spindle 40 and wheel 41. The planet-wheel a2 is loosely mounted upon an arm 43 fixed upon the spindle 16 to intermesh with the crown wheels 36 and 37 with their respective attached spur wheels 35 and 38 having their hubs 35* and 38 loosely mounted upon said spindle, so that the spindle is, by the turning of the handle 1, 1'0- tated by the wheel 17, in one direction, while the counting mechanism is not moved because the intermediate wheels connecting one of the crown wheels to the counting mechanism have such a velocity ratio that they are self retarding. But if the counting mechanism rotates while current is consumed the crown wheel belonging to it will be rotated while the drum 2 is at rest; this rotation of the crown wheel returns the arbor 16 to its original position. The retardation of the counting mechanism may be effected by locking pawls in any suitable manner while the handle 1 is rotated.

The spindle 16 carries a disk 18 and a pin 15 is secured to the lever 14 and bears against the inner edge of the said disk and operates the lever 14 in such a manner that the pin 13 on the said lever bears against the pin 11 of the switch which is brought into the closed position by the spring 6.

the switch 8 is closed.

hen the said pin 15 enters a notch 21 in the inner edge of the disk 18, the lever 14 takes such a position that the pin 13 is disengaged from the pin 11 and by the force of the spring 1, the switch being no longer kept back by the engaging of the pins 11 and 13, rotates until pin 11 bears on pin 12 on the lever 14. Pin 12 now holds the switch in the switched out position. As the rotation of the handle 1 causes the rotation of the arbor 16 and disk 18, the pin 15, if it be engaged with the notch 21 of the disk, will be raised out of the said notch so that the resulting movement of the lever 14 releases the pin 11 which is brought, by the spring 6, into the circuit closing position and If the switch be closed the coins subsequently inserted in the apparatus do not move the lever 14, but the lever 14 remains in this position and the pin 13 keeps the switch in the switched on position, but each coin introduced en ables the disk 18 to be turned farther so that the notch 21 is moved farther away from the pin 15 and the time during which the switch remains closed is correspondingly longer.

In accordance with this invent-ion, the arbor 16 has secured to itself the one end of a spiral spring 20 the other end of the said spring being fastened to the frame of the apparatus at 20*. The rotation of the arbor 16 winds up the spring 20 and the arbor 16 tends to turn backward (indicated in Fig. 1 by an arrow) and to move the counting mechanism forward. But as a num ber of wheels are inserted the arbor 16 and the counting mechanism, which wheels have, as already stated, a retarding action, the force of the spring is not sufficient to automatically drive the counting mechanism but only acts against the frictional resistances between the arbor 16 and the counting mechanism and thereby enables the counting mechanism to operate even if the consumption of current be very low, because it has not more to overcome the resistances through its own driving power which work is done by the wound up spring 20. The sensitiveness and the accuracy of the indications of the counting mechanism are therefore much greater than they would be if this spring were not introduced. As the frictional resistances are constant, the spring should be so designed that it exerts a practically constant force. This spring 20 fulfils also another function: if the arbor 16 be brought back into its original position by the counting mechanism, the pin 19 attached to the disk 18 tends to push the pin 15 of the lever 14 into the notch 21 so that the pin 11 of the switch is released from the pin 13 and the switch is opened by the tension of the spring 6 which turns the switch until pin 11 bears on pin 12. The pushing back of the lever 14 would be done that too much current would be taken from I the mains. For this reason the lever 14 is not returned to the switched out position by the counter itself but by the wound-up spring 20 which presses by the pin 19, the lever 14 into the notch 21, so that the pin 11 is released from the pin 13 and the spring 6 can turn the switch open without an additional load being thrown on the counting mechanism. As the spring 20 acts on the disk 18 without the assistance of intermediate gear, the tension of this spring is sufficient to shift the lever 14. The spring 20 has therefore in this case to fulfil a double function, namely: firstly, it opposes the frictional resistances of the intermediate wheels arranged between it and the counting mechanism, and thereby relieves the counting mechanism from the additional friction, and secondly it causes the shifting of the lever 14 to the position thereof which corresponds to the opening of the switch 8, which opening is effected as aforesaid.

The specific embodiment of the prepayment mechanism described above forms the subject of my pending application Serial No. 347,433, filed December 12, 1906.

This invention differs from others relating to prepayment electric meters in that the counting mechanism itself performs no work which would throw an additional load on it, special sources of stored energy being provided therefor by hand.

Having now described my invention what I claim is:

1. In a prepayment electricity meter, in combination, a shaft adapted to be turned in one direction proportionately to the number of coins introduced into the meter and to be returned to initial position by a counting mechanism for measuring the electric current, a cam member on said shaft, an electrical switch, mechanism intermediate said switch and cam member whereby the switch is adapted to be reciprocally actuated as the cam member moves respectively into and out of initial position, and a spring applied to said cam member and adapted to aid the counting mechanism in returning the cam member to initial position and also acting through said cam member to insure the opening of the switch.

2. In a prepayment meter, a rotary actu ator adapted to be freely rotated by hand, a controller shaft, a controller member carried thereby, an intermediate shaft carrying a spring for turning the controller shaft, gearing connecting said spring with the con troller shaft, a frictional driving connection between the actuator and said intermediate shaft, a letoff mechanism for said controller, a cam member for governing the letoff mechanism, and connections, brought into operation by introduction of a coin, between the actuator and the cam member.

3. In a prepayment meter, a rotary actuator adapted to be freely rotated by hand, a controller shaft, a controller member mount ed thereon, an intermediate shaft carrying a spring for turning the controller .shaft, gearing connecting said spring with the controller shaft, a frictional driving connec tion between the actuator and said intermediate shaft, a let-off mechanism for said controller, a cam member for governing the let-off mechanism, and a spring applied to said cam member in a direction to return the same to initial position when turned therefrom to actuate the controller member.

at. In a prepayment meter, a rotary actuator adapted to be freely rotated by hand, a controller shaft, a controller member mounted thereon, an intermediate shaft, gearing for actuating the controller-shaft having a member loose upon the intermediate shaft, a spring connecting said intermediate shaft with the member of the gearing mounted thereon, a frictional driving connection between the actuator and said intermediate shaft, a let-off mechanism for said controller including a vibratory lever with means for alternately engaging the rotary member carried by the controller shaft, a cam member having two operative portions for alternately engaging said vibratory lever in governing the let0lf mechanism, and means for actuating said cam member.

5. In a prepayment meter, a rotary actuator adapted to be freely rotated by hand, a controller shaft, a controller member mounted thereon, an intermediate shaft, gearing for connecting the controller-shaft and intermediate shaft and including a toothed wheel fixed upon one of said shafts and an intermeshing toothed wheel loosely mounted upon the other of said shafts and yield ingly connected therewith by means of a coiled spring, a frictional driving connection between the actuator and said intermediate shaft, a lateral pin or projection carried by the controller-shaft, a pluralarmed lever mounted upon a fixed fulcrum and having two arms embracing the controller-shaft and adapted to alternately engage the pin or projection of the controllershaft and provided with an arm carrying a lateral pin, a cam-member formed with an annular cam-shoulder provided with a notch for engagement of the lateral pin of the pluralarmed lever and with an adjacent lateral pin adapted to engage said lever as its pin enters the notch in the annular camshoulder, whereby the cam serves as a stop for the plural-armed lever and said lever affords a stop for the cam in arresting their respective movements in initial position, and means for actuating said cam.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

HERMANN ARON. \Vitnesses:

HENRY HASPER, VVOLDEMAR HAUPT. 

